#include <iostream>
#define SIZE 100
using namespace std;

void read();

double numbers[SIZE];
int i, n;

int main()
{
	double s;
	cout << "n = ";
	cin >> n;
	
	read();
	
	for(i = 0; i < n; ++i)
		s += numbers[i]; 		
	
	cout << s / n;
	return 0;
}

void read()
{
	for (i = 0; i < n; ++i)
	{
		cout << "number[" << i << "]=";
		cin >> numbers[i];
	}

}
